Aluminum alloy for heated bed?

DeltaCon

Edit - The other side of the coin http://richrap.blogspot.co.uk/2016/02/glass-3d-print-build-surfaces-are-not.html

Nice info, thanks!

DeltaCon

Mostly I print with a bed temperature of 70C, but I had a phase of printing ABS using 110C. The bed is 5mm thick 330mm diameter aluminium with a 350W AC mains heater on the underside, and I had 4mm thick 330mm diameter float glass on top of it.

Okay, I use the same thickness alu sheet with PEI directly on top. It has enough thermal mass to keep it (autotuned) within 1,5 degree variation. Also the variation across the bed is very little. Where I often got more than 7 degrees difference from center to bed using only boroglass on the PCM, that has been reduced to not more than about 2 degrees. So 5mm alu does in fact do a nice job. However I think that the thin heatspreaders you see in some shops are really too thin. It is mass that counts…

@dc42:

I also know of someone using a 3mm 210x210mm sheet directly on top of a PCB heater at 100C bed temperature, but I don't advise that.

Yes, that really is the danger I wanted to warn about. Seeems that a good thick alu heatspreader fixes that, but on the other hand a good thick heatspreader makes the glass unneeded if you want to use it together with PEI. I have a second bare heatspreader, in case there would be a time that I would want to print on bare glass. But PEI works just fine for me up till now. No tricks at all needed for PLA, ABS and PETG. Have not tried others yet

timcurtis67

I'm another float glass user. Been using float glass for 3-1/2 years of printing at temps from 60C to 100c without issues. I too "hot swap" the glass bed when running production runs of parts. I've broken 3 plates in my years,

1 because I dropped an extruder motor on it. The second was when I stepped on on I had sitting on the floor by my printer. And the third was broken by a large part that stuck so well it actually snapped the plate when it cooled. It didn't shatter it just snapped in half.

Martin_S

I'm a PEI fan. It's been around 3 years since it was installed and it stills performs like a champ. Others suggests to sand it, but personally, never did that and prints sticks great to it. Just clean it with some isopropyl alcohol and it's good to go.

dc42

On my Ormerod I print PLA on plain uncoated float glass. I wipe it with distilled vinegar between prints. It works very well with good-quality PLA filaments if you prepare the glass correctly and avoid finger-marking it. Bit some PLA filaments won't stick to it.

On my delta I have one float glass bed with PEI on top and another with PrintBite on top. I mostly use the PrintBite one, because the PLA I use sticks too well to PEI.

My Scara printer prints on to unheated blue tape on the desk in front of it.

cicloide2

@Martin_S:

Hi all, quick question, I'm about to have some parts water-cut and need to buy the aluminum sheets.
I wanted to buy MIC6 but it seems that it doesn't exists around here, so what would be a good alloy for the heated bed?

6061? 5083? 7xxx? other?

Thanks in advance
Martin

I do not know if he already solved it, I'm new here. Undoubtedly I would choose aleaceon 6061, you just have to think about which temple T will ask for it, 6061 is used in aircraft, it is secret is the temple, in T4 it would be well machined well.